Anatomical evaluation of the axillary approach to the axillary and radial nerves for nerve transfer or nerve grafting procedures

Abstract

Having detailed anatomical knowledge when performing surgeries, is crucial to ensure a successful outcome. This is especially true when undertaking relatively new procedures. Even though nerve transfers and nerve grafts have been performed on the different parts of the brachial plexus for some time, nerve transfer and grafting procedures involving the axillary and radial nerves using a newly proposed axillary approach has not yet been fully studied. This study provides some enlightenment to the anatomy surrounding the axillary approach, with special regard to the axillary and radial nerves and their branches. The axillae of 51 (26 female and 25 male) formalin fixed cadavers were bilaterally dissected using a simulation of the axillary approach, which has been described to gain access to the brachial plexus in a clinical setting. Following which, various distances between easily identifiable anatomical landmarks and relevant neurovascular structures were measured, and observations regarding the relationship of these structures to the landmarks were recorded. This study found that the axillary nerve and its anterior and posterior divisions, as well as the radial nerve with its nerve to the long head of triceps brachii muscle could be easily identified however, their proximal parts were situated fairly deep and therefore were difficult to expose. Methods such as the musculo-arterial triangle described by Bertelli et al., which was designed to aid in identification on localization of the axillary nerve was also assessed; it was found to be relatively successful, however more consistent landmarks might be considered. In conclusion this study found that the axillary approach may serve as a reliable and safe method to reach the axillary and radial nerves, as well as their branches, allowing for adequate exposure when considering a nerve transfer or graft.